vseae / launchpeg

Launchpeg

This repository contains two ERC721A implementations:

• Launchpeg implements a fair and gas efficient NFT launch mechanism in three phases: dutch auction, allowlist mint and public sale.
• FlatLaunchpeg implements a simple minting NFT contract with an allowlist and public sale phase.

Both contracts implement BatchReveal developed by Tubby Cats. This is an on-chain shuffling algorithm used to reveal NFTs in batches.

How does it work ?

Contracts

BaseLaunchpeg

An abstract contract inherited by both Launchpeg and FlatLaunchpeg. It contains common functionalities.

Each address is allowed to mint up to maxPerAddressDuringMint NFTs.

Launchpeg

The sale takes place in three phases:

It starts with a dutch auction: the price gradually decreases over time until the end of the phase or when all tokens allocated are sold.

The allowlist mint starts right after the dutch auction: whitelisted users can mint at a discount from the last auction price from the previous phase.

Once the allowlist mint ends, all remaining NFTs are sold in the public sale at a discount from the last auction price.

FlatLaunchpeg

In this contract, the sale is simpler; all NFTs are minted at a fixed price and takes place in two phases: an allowlist mint and public sale that can be enabled / disabled with setPublicSaleActive.

ERC721A from Azuki:

Implements a more efficient way of minting several NFTs. The number of NFTs minted at once is limited by maxBatchSize.

You can find details about ERC721A here: https://www.erc721a.org/

Batch Reveal from Tubby Cats:

Reveals NFT URIs pseudo-randomly for now and efficiently. Reveals are done by batch so people don't have to wait the end of the sale to see their NFTs. Reveal can be triggered by anyone under certain conditions, reducing the risk of randomness manipulation.

Reveal can be implemented in two ways:

• Enough NFTs have been minted (we don’t want to reveal unsold NFTs)
• Reveal start date has passed

"Revealing" a batch means that a random number will be drawn. This will be the offset that will link the token ID and the URI ID. All the logic afterwards is handled in the tokenURI() view function.

Configuration:

batchRevealSize: Number of NFTs that will be revealed at once

revealStartTime: Date of the start of the NFT reveal

revealInterval: Time interval between two reveals

Scenarios:

💡 revealStartTime = 0 and revealInterval = 0

Users can trigger a reveal as soon as enough NFTs are minted, i.e. batchRevealSize is reached. Anyone can call the function at any time so it reduce the risk of randomness manipulation even without Chainlink VRF.

💡 revealStartTime = D+3 and revealInterval = 30mins

Users can trigger a reveal 3 days after the sale begins. They will be able to reveal one batch every 30mins, assuming NFTs have been sold.

💡 Collection doesn’t sell out

If the collection doesn’t sell out people will be left with unrevealed NFTs. Project owner can unlock the situation by forcing the reveal. Unsold NFTs from the same batch will be revealed as well.

Setup

We use Hardhat to develop, compile, test and deploy contracts.

# install dependencies
yarn

Testing

yarn test # run test
yarn coverage # run coverage report from solidity-coverage

Deploy contracts

There are two environment variables to define in the .env file:

# The contract deployer
DEPLOY_PRIVATE_KEY=
# The snowtrace API key used to verify contracts
SNOWTRACE_API_KEY=

Deploying LaunchpegFactory and LaunchpegLens is made using yarn hardhat deploy. Creating Launchpegs then uses deploy scripts: The deploy task takes a config file as parameter. This file contains all the required parameters to initialize a contract.

There are two templates available in /tasks/config: example.json for Launchpeg and flat-example.json for FlatLaunchpeg.

Once the configuration is ready, you may run:

yarn compile

yarn deploy-launchpeg-fuji --config-filename <config-filename>
yarn deploy-flat-launchpeg-fuji --config-filename <config-filename>

yarn verify-fuji 

Test coverage

Test coverage on current commit fc0f3b5 is the following :

File	% Stmts	% Branch	% Funcs	% Lines
BaseLaunchpeg.sol	98.61	91.3	94.74	94.68
BatchReveal.sol	100	100	100	100
FlatLaunchpeg.sol	95.24	91.67	80	92.59
Launchpeg.sol	96.97	92.86	90.91	95
LaunchpegFactory.sol	100	100	100	100
All files	98.51	94.12	94.34	96.58

Coverage was calculated by the solidity-coverage plugin from hardhat.

License

MIT